Do I really need a 5k display?

Thanks to this forum I have a much better understanding of the pitfalls when using C1 with a 5K iMac.

My current system consists of a late 2013 27†iMac with High Sierra, quad core i5, 24GB memory, 1TB Fusion drive and Nvidia GT4 775M 2GB graphics.

I use two 2560x1440 displays, one in the iMac for the viewer and the other is a Cinema display for browsing and adjustments.
The performance is absolutely fine for an amateur and I would be happy to continue for quite a while longer.

However the spinning HD will not spin forever after nearly seven years of continuous, use so I need to plan for a rapid upgrade when it or something else dies.

I would appreciate the wider colour space of a new monitor but I don’t think that I need a 5k display. I am managing fine with my current display and using 1:1 zoom when needed while adjusting.
The final output of my images is on a DP3 colour space iPad, a DP3 Samsung TV and for some images an Epson SC600 Printer.

So, I thought, how about a mac mini with a Benq 2560x1440 DP3 display?
According to Apple the Intel UHD Graphics 630 will easily handle two 2560x1440 displays so my only question is whether C1 will be happy with the integral graphics rather than a discrete graphics card. Especially as C1 recommends at least a discrete 8GB graphics card.

Does anyone out there use a similar mac mini based system?
If so I would be very grateful for a performance review.